There can be little doubt that animal husbandry is an essential aspect of contemporary life. Wool shorn from sheep raised for that purpose goes into garments and accessories which function to keep the wearer warm even in very low temperatures. Light-weight wool garments also function to afford to the wearer stylishness and a contemporary appearance. Wool garments, therefore, prove not only functional, but aesthetically appealing also.
A first step in the manufacture of such garments is the removal of the wool fiber from the sheep. In order to maximize efficiency and economy, a sharp and reliable pair of clippers is necessary.
While it can be seen that clippers serve an important function in a practical operation such as the weaving of woolen goods, they are also an important implement employed in other endeavors involving animals. For example, such appliances are important tools to one who raises and displays show horses. Certainly, numerous other applications also exist where the fur or hair of an animal is to be shorn for some intended purpose.
Because of the coarseness and the strength of animal hair, clipper blades, typically, become dull after very few operations. In some cases, a newly sharpened appliance can have achieved a level of deterioration after only one use in cutting, for example, the mane and tail of a horse so that it becomes necessary to resharpen the cutting blades prior to the appliance being used again. As previously indicated, efficiency is important, and dull blades cause the efficiency to deteriorate significantly.
Commercial services are available for sharpening clipper blades. These services tend to be relatively expensive, however. As one will understand, in view of the frequency at which blades must be sharpened, significant monetary expenditures and time investment can be involved in the business of, for example, raising and displaying show horses.
Certainly, one can attempt to sharpen clipper blades himself rather than sending them out to a commercial sharpening service. Devices and methods known in the prior art, however, make this difficult and, potentially, even more costly than sending a clipper out to a sharpening service. This is so, since someone who is not knowledgeable can damage the blades in his attempt to sharpen them.
FIG. 8 illustrates one tooth of a moveable clipper blade as shown in cross-section. Such a tooth moves laterally as the blade of which it is a part is made to reciprocate. As the moveable blade reciprocates from right to left, the lower surface of the tooth, at sides of which cutting edges are defined, interacts with a corresponding surface or surfaces of teeth of a fixed blade. The cutting edges of upper teeth cause strands of hair to be squeezed between those teeth and cutting edges of lower teeth to effect clipping.
The intent of sharpening is to render cutting edges acute (that is, without any rounding). As a result, interfacing surfaces of the upper and lower blades will move, substantially, in a common plane and the pointed edges of the teeth will closely pass each other to effect a maximum efficiency cutting operation.
FIG. 8 illustrates a tooth 10 of a moveable blade 12, the lower surface of which is substantially planar. As will be able to be understood in view of this disclosure, it would be undesirable to have such a surface 14 with any measure of convexity. The more convexity existing in such a lower surface 14 of a tooth 10 of the upper, moveable blade 12, the duller of the cutting edge of the tooth 10 will be.
Conversely, the lower surface 14 of a tooth 10 of an upper blade 12 might, appropriately, have a measure of concavity, as indicated by phantom line at 16, and still function well for its intended purpose. In fact, if a measure of concavity 16 is provided, the cutting teeth 10 might be even sharper than they would otherwise be. In any event, however, the provision of a measure of concavity would also retard the rapid rendering of the teeth 10 dull, since, even if some of the tooth edge 18 becomes worn, there will still be a tendency to provide an acute angle at the tooth's edge 18.
When novices attempt to sharpen blades, they, typically, fail to recognize that, as they move a blade 12 over a sharpening surface 20, there is a tendency to wobble the blade 12 over the sharpening surface 20 as sharpening is being attempted. As a result, when the lower surface 14 of the tooth 10 is, initially, planar, there will be a tendency to render that surface 14 somewhat convex, and, when the tooth's lower surface 14 is initially provided with some measure of concavity 16, there is a tendency to diminish the degree of concavity. After a number of sharpening operations performed in this manner, the blades can be damaged so that they can be sharpened only by grinding a large portion of the blade surface. As a result, the blade life is significantly diminished.
Another problem in performing manual sharpening operations derives from the nature of abrasive sharpening compound used. It is essential that the compound be used sparingly or undesirabe damage can occur. Too much compound on the sharpening plate will result in a poor cutting edge on the blade's teeth.
It is to these problems and desirable dictates of the prior art that the present invention is directed. It is an apparatus and method which goes far to solve the problems described herein, and it also considers the desirable characteristics which prior experience dictates.